This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cryptococcus neoformans is an opportunistic fungal pathogen and a common source of fungal infections in immunosuppressed patients. In the developing world, mortality from Cryptococcus infections approaches 100%. Treatment of fungal infections such as Cryptococcosis is severely limited, even in developed countries, by a paucity of drugs. The most effective available treatment, intravenous Amphotericin B, is highly toxic. Furthermore, fungal pathogenesis is relatively poorly understood, particularly in comparison to bacterial pathogenesis. We seek to investigate mechanisms of fungal pathogenesis by identifying and investigating extracellular proteins that have the potential to interact directly with the host immune system. To this end, we will isolate and identify by mass spectrometry secreted soluble and microvesicular proteins produced by Cryptococcus neoformans.